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I think this question should have posted a lot of time in this thread but i still need to understand something.. so guys, please bear with it and thanks a lot..

Changing exhaust is it illegal..?
Confirm loud one sure cannot but what about those exhaust that is quiet although is not ori exhaust..

Yesterday, my friend got a saman.. he told my friend that he modified his exhaust.. the problem is, he didnt ask my friend to tekan the minyak... then he saman my friend already.. the...